I found a picture of a delta wing SPAD that I thought looked really cool, so I decided to imitate it. This thing has a 24" fuse, 36" wingspan, a music wire stiffener, and 8" stabilizers. I am planning on powering it with a .25

Don't think a 25 will have enough power
Most people are using 46 and 47 size engines on the CoroRoo and BullDawg.
The pic of the CoroRoo You posted, has an ASP 52S with purple pipe running on an APC 11x9 and taking the manifold down to about 3" made a huge difference to the rpm!
You can find the entire build thread and plans at( You'll have to register to log on )http://www.spadcombat.co.uk/spad/
In the SPAD Builds and Construction forum on page (4) topic miniCororoo

Thanks for the advice, both of you. My airframe is weighing in at about 28 ounces, with the elevon servos installed. It will be right around 2 pounds when I add the RX, battery, and throttle servo. With an engine, the weight should be pretty similar to Microsprint9's bird.

I know that most of the guys building these things are looking for extreme speed. I am looking for a fun flyer that looks different from my other planes. I have a couple of engine choices that I can borrow from other planes. I may try it with the .25FX from my combat spad, and if that won't fly it, I'll try the .46LA off my Four Star. I've been thinking of going to a four stroke on that plane anyway.

Thanks for the advice, both of you. My airframe is weighing in at about 28 ounces, with the elevon servos installed. It will be right around 2 pounds when I add the RX, battery, and throttle servo. With an engine, the weight should be pretty similar to Microsprint9's bird.

Looks like fun. It looks to me that the fold in the verts follows the fuse cut out. If that is so, they will act a bit like down elevator because they are basically a v-tail. Watch for that on launch. It might try to nose in on you. Take another look at the cororoo, and see that the fold in his verts is parallel to the wing. Good luck with the maiden.

Looks like fun. It looks to me that the fold in the verts follows the fuse cut out. If that is so, they will act a bit like down elevator because they are basically a v-tail. Watch for that on launch. It might try to nose in on you. Take another look at the cororoo, and see that the fold in his verts is parallel to the wing. Good luck with the maiden.

I mounted the engine and fit the RX and battery inside the fuse. I reworked the stabilizer mounts to level them out, but they are still a bit crooked. I have a bit of work to do to straighten them out, or I may go back to the drawing board back there.

With everything on it except a couple of screws and pushrods, it weighs exactly 3 pounds. The way our weather's been, it could be a month before this thing gets in the air anyway.

When Your building a new design some people can't handle it and would rather put You down instead of encouraging You to succeed.
Don't let it get You down.
Sounds like Your getting close to the maiden flight.
Eagerly waiting the flight report.
As for the vert stabs, on the CoroRoo they put coat hanger wire in them to get them to hold there shape.
You could also just make a "V" tail out of one piece of coro for the tail feathers.
Jeff[8D]

Mclina:
That's a fine looking delta...good luck with it. I built a bulldawg a couple years ago and never had much success with it, but most people seem to have good luck with the delta's in general. Looking forward to your maiden report.

The V tail was a great idea. I think it looks a lot straighter now. I also fixed the wing - if you look at the original wing bottom picture, it was not symmetrical. I didn't realize it until I had the striping tape on. I took the tape off one side and fixed it.

All it's missing now are the elevon pushrods. It is balanced about 1/2" in front of the CG on the cororoo plan. I think I will leave it there for the maiden flight.

I've been following and reading your thread and have built a cororoo too !!! I have a question about the construction of the elevons though.

On the plans it says

"Once the flaps have been folded over and glued, the elevon outer skins can be
made, cut a strip of 2mm corro approximately 76mm wide, flutes running the
76mm direction, and long enough to make 2 elevons. Score a center line and
and fold over, exactly as you would do when making a wing leading edge, these
are then glued to the elevon hinge parts, as per the pictures in the build thread.
This first "

I've folded over the top flaps, but am unsure how the elevon outer skins are made and attached. When I glued in the 4 mm. elevons between the top and bottom skins, I thought this was to be the elevons. Is there to be a 2mm by 76mm top skin glued to the top of this ?

I'm anxious to hear about your maiden flight !!! how are you planning to launch the cororoo ? Possibly hand launching like the PBF ? Looks little scary with a screaming .46 on the nose !!!

I've folded over the top flaps, but am unsure how the elevon outer skins are made and attached. When I glued in the 4 mm. elevons between the top and bottom skins, I thought this was to be the elevons. Is there to be a 2mm by 76mm top skin glued to the top of this ?

Yes , 2mil folded and wrapped over and glued to the top and bottom of the 4mil elevons , it helps stiffen the elevons and makes them even with the top and bottom skin.
Making the elevons 4mil thick.
Jeff

Last picture, I promise. I added some stripes to the tail, and took a shot from the side to show the profile of the stabilizers. I installed the elevon pushrods and programmed the radio. It is now 100% ready to fly. We got 8" of snow last night, so it will be a while before the maiden. I will have one of my kids shoot a video of the maiden, and I'll post it if it's not too embarrassing. OK, I'll post it even if it is.